In intraocular blood circulation, ophthalmic artery enters into orbit and branches to central retinal artery, lacrimal artery, posterior ciliary artery and anterior ciliary artery. Then, the blood circulation flows out of the eye through retinal central vein, vortex vein and ophthalmic vein. Anterior ciliary artery connects to blood vessel systems of choroid, optic disk, iris, ciliary body and the like. Therefor, it is known that, when the blood vessel systems are damaged, diseases such as glaucoma (in particular, open angle glaucoma and normal pressure glaucoma), pigmentary retinal degeneration, macular degeneration, ischemic optic neuropathy, choroid diseases following iridocyclitis, and retinochoroiditis are induced, and visual functions are damaged.
As hitherto known factors which cause intraocular blood circulatory disorders, among physiological active substances produced in vascular endothelial cells, there are those contacting blood vessel smooth muscle cells such as endothelin, thromboxane A2, angiotensin II and endogenous amines (dopamine, epinephrine, serotonin and the like). However, ocular blood flow varies largely due to difference in species, individuals and ocular tissues. In addition, ocular circulation measurement is still developing. Then, factors which cause intraocular blood circulatory disorders have not yet been fully elucidated.
Currently, for chemotherapy of diseases accompanied with ocular blood circulatory disorders, tocopherol nicotinate which is vitamin E medicine, micro-circulatory improving medicine such as pentoxifyline, and various steroids are administrated orally. However, there are problems such as insufficient ocular circulatory improving activity, and side effects, for example, hypotension and gastrointestinal disorders. It is also known that diseases such as ocular hypertension and closed angle glaucoma are caused by aqueous humor circulatory disorders. In glaucoma, the ocular hypertension causes disorders of the axon of optic nerve, which results in visual function disorders such as disorders of optic disk and abnormal visual field. For treatment of glaucoma, there are instillation of cholinergic agents whose typical example is pilocarpin which contracts ciliary muscle to stimulate outflow of aqueous humor; instillation of sympathomimetic agents such as epinephrine and dipivefrine which inhibit production of aqueous humor; and instillation of sympathomimetic .beta.-blockers such as timolol, pindolol and carteolol; as well as oral administration of carbonic anhydrase inhibitors such as acetazolamide; and instillation of prostaglandin derivatives which promote uveoscleral outflow of aqueous humor by relaxing of ciliary muscle to promote outflow of aqueous humor. However, these drugs have problems such as various side effects depending on their respective activities.
Further, recently, many persons have been required to continue working at a short visual range as a factor of the living environment. This has caused ciliary muscle tension, resulting in visual function disorders such as refractive errors, for example, tonic accommodative myopia and myopia. Although instillation of control paralytic agents such as atropine and tropicamide have been tried to inhibit progress of myopia, this treatment is not popularized in the clinical field because of unreliability of effects and side effects such as mydriasis.